Process for the manufacture of hard soaps.



UNITED STATES PATENT OFFICE.

JOACHIM LEIMDURFER, F BUDAPEST, AUSTRIA-HUNGARY.

PROCESS FOR THE MANUFACTURE OF HIARD SOAPS'.

No Drawing.

To all whom it may concern Be it known that I, J OACHIM LEIMDoRFER,

a subject of the King of Hungary, residing at V1 Vaczi ut 96, Budapest, in the Kingdom of Hungary, have invented certain new and molecules are enlarged by polymerization.

Such compounds are very generally employable in soap manufacture as will appear from the following explanations. In the first place they permit of the manufacture from what are called grain fats of hard paste soaps which it has hitherto only been possible to manufacture from so-called paste fat.

As is known the oils and fats utilized in the soap industry are divided into two classes from the point of view of the special requirements of this industry. The first class is the grain fats and the second class the paste fats. The greater part of the natural oils and fats belong to the grain fat class while only two technically employed oils or fats are enumerated among the paste fat class, that is to say palm-nut oil and cocoa nut oil.

wherever these expressions grain fats and paste fats occur hereinafter, they are respectively to be construed as having the meanings defined in the preceding sentence.

The paste fats differ ffiim the grain fats in that they are saponifiable with concentrated lyes at low temperatures or are utilizable in cold and semi warm saponification. \Vhen saponified separately they re quire considerably larger quantities of salt for graining them from the aqueous solution than thesaponified grain fats require and the soaps obtained from them may contain large quantities of colloidal solutions and solutions of electrolytes owing to the difficulty of effecting the graining.

The colloidal solutions and solutions of electrolytes are technically designated load- Specification of Letters Patent.

It is to be understood that intended to contain large quantities of loading lyes, or salts of given concentrations, at the present time only paste fats can be employed, either alone or mixed with grain fats. Thus for example for producing coldstirred cocoanut oil soaps, paste soaps, half grain or Eschweger soaps and also mottled soaps, the presence of cocoa and palm-nut oil is necessary in variously high percentages of the quantity of added fat. These ioaps cannot be produced from pure grain ats.

It is worthy of notice that when cocoa and palm-nut oils are deglycerinized and boiled to form grain soaps and when it is desired to add large quantities of loading material to the grained soaps thus obtained, as is possible in the case of paste soaps from the same fats, it is found that it is impossible to effect what is called the after loading of the grain soaps to this extent.

Experiments that have been undertaken have led to the surprising result that the resisting capacity of the alkali salts of the fatty acids to electrolytes in aqueous solution is considerably increased when halogen, hydroxy or acid groups enter the carbon Patented May 4, 1915.

Application filed March 28, 1912. Serial No. 686,8(l4.

chain of the fats or fatty acids, or when the I molecule of the fats or fatty acids is enlarged by polymerization. Such modified fats and fattyacids are known parse. In particular the Turkey red oil obtained from castor oil which latter has, it is true, already been used in the manufacture of certain liquid, emulsion-like or gelatinous soap-like products as an added substance together with other fatty substances or alone, still these products cannot in any sense be termed technical, hard or bar soaps. Now the process which is contemplated by the present invention resides in the fact that the above added substances are introduced into the soap mass in such a manner that both these substances and the basic substance of the soap are substantially completely saponified so that technical hard or bar soaps are formed. This employment of the said added substances presents various advantages of importance both from the technical and the industrial point of view. Thus for example it is found that a grain soap produced from grain fats and containing completely saponified Turkey 'red oil behaves quite similarly as regards electrolytic solutions to a cocoa-nut or palm-nut oil soap. A palm-nut oil or cocoa-nut oil soap,

however, which contains completely saponilied Turkey red oil or hydroxy, halogen or sulfo fatty acids, behaves relatively to electrolytes precisely as if it were a paste soap and in these circumstances it is possible to increase the soap with loading substances to a far greater extent than would be possible without these saponified additions.

The resisting capacity of soaps relatively to electrolytic solutions is not only of importance from the point of view of t e capacity for increasing soaps or their reception of loading substances, but in other respects plays an important part in the soap industry. Thus, for example, it is known that soaps, and grain soaps in particular, experience a structural modification when stored owing to the fact that they partially coagulate, whereby an aqueous solution containing an electrolyte is separated and tends to cause the soap either to sweat or to go moldy. If such soaps receive one of the said saponified additions, owing to the increased colloidal resisting capacity these phenomena no longer exist. It is also known that, owing to the asymptotically proceeding saponifying reaction and to hydrolysis, soaps must always present a definite excess of alkali. In the presence of the said saponified additions it is, however, possible to neutralize the soaps without risk of hydrolysis, which is of great importance and exceedingly advantageous in the case of toilet soaps in particular.

Owing to their great sensitiveness relatively to electrolytes and to the solubility of the lather of the soaps manufactured from them, it has hitherto only been possible to use very small quantities of certain oils in soap manufacture, thus for example vegetable tallow, colza oil, dodder seed oil. Mixed with the said additions, however, all fats can be employed for the production of any hard soap even without palm-nut oil and cocoa-nut oil. The said additions are also utilizable with advantage in the manufacture of hard soaps adapted for washing in seawater and other waters containing a high percentage of electrolytes. If a soda soap contains the said saponified halogen, oxy, hydroxy orsulfo fats or fatty acids or polymerized products, palm-nut oil or cocoanut oil soaps are specially suited for use with sea-water, Finally, it is known that soaps loaded with water-glass must contain a very considerable excess of free alkali corresponding to the quantity of water glass. The reason for this is that in ordinary soaps loaded with water glass two colloidal systems form. The system water glass +NaOH+H O absorbs fatty acid salts while the fatty acid salt+NaOH+I-I,O absorbs water glass. From this it follows that in both systems a corresponding excess of alkali must be present. If, however, the fatty acid salt system or the soap system is insensitive to electrolytes, it is able completely to absorb the water glass and merely that excess of alkali is necessary which corresponds to the fatty acid salt-l-soda lye-l-water glass-l-water system. This is of very great importance from the point of view of sparing the fibers.

From the above statements it appears that the process in accordance with the present invention resides mainly in the fact that the resultant products contain only normal fatty acid salts in the percentages usual in the soap industry and these products are hard soaps. If this condition is not fulfilled, soaps are produced which contain unsaponified fat and which consequently are discolored, soft and unpleasant to the touch and which when stored become rancid.

Emamples.

I. 100g. of bone fat, 100g. of neutralized Turkey red oil and 65g. of soda lye at 40 B, are heated in a water bath and left for some time in a hot state or stirred in order to shorten the duration of the reaction. In increasing the temperature and augmenting the reaction mixture a somewhat vigorous reaction takes place and a slightly alkaline soap paste is obtained which when it cools forms a firm hard soap. It can be assumed that the saponification of the bone fat, which cannot of itself be saponified with such strong lye, is rendered possible owing to the fact that this fat is first of all dissolved with the Turkey red oil employed or enters upon a colloid superficial development by absorption, which condition is favorable for the saponifying reaction. The saponifying reaction of the bone fat with the lye develops sufficient heat for saponifying all fat present in the reaction sphere into normal fatty acid salts.

II. 100g. of sesame oil, 30g. of 70% sulfonated train oil and 57-60g. of soda lye at 40 B. are saponified as indicated in (I). The soap paste thus obtained sets into a solid, hard soap although neither sesame oil itself, nor Turkey red oil itself forms equally hard soaps with the same concentration.

III. 100g. of olive oil, 15g. of digested castor oil fatty acid, 25g. of 62% Turkey red oil, 64g. of soda lye at 40 B. are treated as in example (I). A highly viscous soap paste is obtained which furnishes a hard soap.

IV. 50 parts of 60% Turkey red oil are heated to 80 C., and 52 parts of soda lye at 38 B. and 100 parts of water glass at 86 B. are added. The mixture is heated to 80 C. and 100 parts of animal tallow heated to 80 C. are added. The mixture is circulated several times and after 15 to 30 minutes a completely saponified stringy soap paste is obtained such as can be manufactured from palm-nut oil or cocoa-nut oil.

The following are examples of the application of glycerids and fatty acids, containing halogen:

The word chlorinated, hereinafter used, is intended to mean a chlor addition product which, through adding chlor, is produced in such a manner that the chlor joins the unsaturated combinations of the fat or the fatty acid, for instance, according to the following formula:

\ Oleic acid. Chlorinated oleic acid GH;(OH .O H OH (OH .CHCi

H.C.OH .OOOH OlH.O.CH .COOH

V. 100g. of sesame oil, 50g. of chlorinated olein, 50g. of sulfonated olive oil are mixed and heated to from S090 C. To the heated mixture are added 150g. soda lye of 30 B. Reaction takes place and a hard soap results.

VI. 100g. bone fat, 50g. hydroxylated fatty acid, prepared by treating chlorinated olein with water under pressure, and 50g. nitro-oleic acid are mixed and heated to from (SO-80 0. 200g. soda lye of 25 B. are added. The result is also a hard soap.

VII. 100g. tallow, 100g. polymerized ricinoleic acid and 100g. sulfo-ricinoleic acid are mixed, heated and 210g. sodium hydrate of 30 B. are added. A. hard, completely saponified product is obtained.

It has also been' found that glycerids, fatty acids or derivatives thereof, the carbon chain or molecules of which contain halogen, hydroxy or acid groups or whose molecules are enlarged by polymerization can be utilized'with advantage in the manufacture of hard paste and grain soaps not only in the manner described but also in I other ways. These methods of employment can be divided into three groups.

I. The first group relates to the utilization of fatty acids for the manufacture of hard paste soaps. It is known that at the present time practically utilizable hard paste soaps can be manufactured both by agitation at a low temperature and also at higher temperatures exclusively in employing triglycerids or natural fats and oils, whereby these substances must be used alone or atleast in excess by weight as compared with the fatty acids that may eventually be mixed with them. Thus, for example, in the case of cold-agitated soaps, for which only cocoa-nut oil is utilizable, the free fatty acids contained in the natural oils are frequently eliminated prior to the saponification process. In the-case of other soaps also at least 50% of neutral fat must be em'- ployed in order to obtain even a moderately useful soap. e

In the c ld or semi-warm saponification of free fa ty acids with the usual lyes, lumps are formed which cannot be eliminated: from the soap; they absorb lye and fatty acids and produce marks and blemishes in the cooled soap and, as neither the fatty acid nor the lye is completely combined, when the soap is stored unpleasant alterations occur in it and render it unmarketable. On the other hand, however, the elimination of the glycerin from the fats prior to their saponification would be highly advantageous from the point of view of carrying on the manufacture profitably and it is a pressing requirement in the soap industry to extract this costly material from the fats and thereby reduce the cost of manufacturing the soap. Now it has been found that the manufacture of such paste soaps exclusively from fatty acids is possible and that accordingly the total quantity of the paste can be extracted from the fats without the quality of the resultant soap suffering" thereby. This result is attained by the coemployment of sulfo fatty acids or polymerized sulfo fatty acids or halogen, hydroxy, fatty acids. If, for example, 50 parts of these compounds for example sulfo fatty acids made from castor oil, train oil, sesame oil or other oils are added to 100 parts of tallow fat acid or other fatty acids, this mixture consisting exclusively of fatty acids and sulfo fatty acids and the like can be completely saponified by means of lye of any desired concentration without the formation of lumps. From this it appears that the sulfo-fatty acids behave quite differently from palm-oil or cocoa-nut oil or their fatty acids as in these conditions the semi-warm saponification cannot be carried out either with palm-nut oil or cocoa-nut oil and far less with their fatty acids.

First 6;rampZc.100g. of olive oil fatty acid. 30g. of polymerized and sulfonated castor oil fatty acid. 60g. of soda lye at 40 Be are heated in water bath and left for some time in a hot state or agitated. A slightly alkaline dense soap pastev is obtained which sets to form ordinary hard soap.

Second emample.100g. of tallow fatty acid. 100g. of Turkey red oil produced from glycerids or preferably from fatty acids. g. of soda lye at 40 B. are saponified in a hot state as in example 1 and furnish a perfect hard paste soap.

In carrying into practice the processes described in examples 1 and 2 it is advisable in the first place to heart the constituents separately to to and then to mix them.

II. The sulfo fatty acids or the oxidized and polymerized products and mixtures thereof can advantageously be utilized for manufacturing soaps without graining the soap paste; the proportion of fatty acids and alkali in such soaps corresponds to that of a grain soap. As is known in boiling grain soaps it is usual to employ free fatty acids and carbonate of soda for saponifying them instead of soda lye. The saponification is effected with a concentrated solution of sodium carbonate and when saponification has been completed a soap paste is obtained containing about 50 to 55% of fatty acid. Generally soda lye is added to this paste until the residual tri-glycerids are saponified and a suitable quantity of free alkali is present in the product. The super alkaline soap paste is now grained whereby according to requirements grain soap and soap paste or grain soap and soap lye are formed. Now in this manner the percentage of fatty acid in grain soap amounting to 63 to 64% can be obtained. The process entails loss of time and material, however, while in utilizing the additions already mentioned great economies in both directions are possible. The percentage of fatty acids of the sulfo fatty acids is variable. Their percentage of fatty acids can be increased or diminished within relatively wide limits according to the process used in sulfonating and washing. For example if train oils sulfonated and then washed with twice the quantity of water as compared with the train oil after neutralization with soda lye at 40 B. a product is obtained which contains about 80% of sulfo acid. This fact forms the basis of the following process. The fatty acids are saponified by means of carbonate of soda and to the soap paste thus obtained such a quantity of a sulfo fatty acid containing a high proportion of fatty acid is added that the proportion of fatty acid in the mixture attains the usual fatty acid proportion of grain soap. After mixing sufficient lye is added for the complete saponification together with the usual excess of alkali (0.1 to 0.2%) the mixture is then saponified in heating until the formation of normal fatty acid salts and is then allowed to cool. A paste soap is obtained containing the same proportion of fatty acid as a normal grain soap and time, material and labor are economized.

III. Finally, the invention relates to the manufacture from finished grain soaps of durable grain soaps with a proportion of the added substances frequently referred to above. If in manufacturing grain soaps in addition to the usual addition of fat and caustic lye or carbonates it is desired to employ sulfo fatty acids and the like and to effect the saponification in the usual manner the resultant product would be quite useless. Owing to the long boiling period at ordinary atmospheric pressure or alternatively the continuous high temperature a portion of the sulfo fatty acids would decompose. Very large quantities of cooking salt would be necessary for graining the soap and the grained soap would absorb very large quantities of salt (3 to 7%) so that the soap would not lather when used. The greater part of the sulfo fatty acids would remain behind in the soap paste and it would only be possible to grain this part with the greatest loss. The resultant salt lye would not gelatinize and although it appears clear both when cold and when hot it contains 1 to 35 of dissolved fat which could only be recuperated by acidifying. The large quantity of dissolved cooking salt, however, renders the acidification somewhat expensive and furthermore the acidification would again decompose the sulfo fatty acids which would render it necessary again to sulfonate them. On the other hand if an attempt is made to add sulfonated fats or fatty acids and the like to ready-prepared grain soaps the fats and fatty acids remain therein unaltered and unsaponified. When stored such soaps become spotted and smell unpleasantly and this always shows itself by their becoming rancid in store. Finally when the soap is stored, oil becomes separated on its surface and the lathering capacity of the soap is diminished to a very large extent. Now in order to produce normal grain soaps from. fats of any kind mixed with the modified fats and fatty acids already referred to, whichsoaps present the properties of soaps made from palm-nut oil and cocoanut-oil in combination with other fats, the procedure in accordance with the present invention is as follows:-The usual fats are saponified with carbonates or caustic lyes an excess of alkali being avoided as far as possible. The weak paste is grained and left for some time to separate. Hereupon the salt lye is extracted and suitable quantities of sulfo fatty acids and the like or their neutralized salts are added to the Weak grain and during a short boiling so much caustic lye is added that the excess lye of a normal grain soap is reached or the soap may even appear neutral. A. neutral soap obtained in this manner contains neither free fat nor free lye as the asymptotic course of the saponifying reaction is conducted in such a manner as to obtain a minimum which cannot be detected analytically.

l/Vhat I claim as my invention and desire to secure by Letters Patent of the United States is l. A process for the manufacture of hard soaps, which consists in adding a saponifiable substance capable of increasing the resisting capacity of the alkali salts of the fatty acids to electrolytes in aqueous solution to one of the usual substances forming the basic constituent of the soap, and in treating the mass with a quantity of alkali corresponding to the formation of normal fatty acid salts and in such excess as may be technically necessary to produce complete saponification.

2. A process for the manufacture of hard soaps which consists in saponifying a substance forming the basic constituent of the alkali salt, together with a saponifiable addition capable of increasing the resisting capacity of the alkali salts of the fatty acids to electrolytes in aqueous solution,

which acts to increase the colloidal resisting capacity of the soap, by means of an alkali in such excess quantity as may be technically necessary for the formation of normal fatty acid salts and for complete saponification.

3. A process for the manufacture of hard soaps which consists in adding to an ordinary fatty substance, a saponifiable substance to render the soap system insensitive to electrolytes, and in producing complete saponification of said substances by an alkali in such excess quantity as may be necessary for the formation of normal fatty acid salts and also for complete saponification.

4. A process for the manufacture of hard paste soaps which consists in adding to a fatty acid a supplemental saponifiable sub stance capable of increasing the resisting capacity of the alkali salts of the fatty acids to electrolytes in aqueous solution, and in treating the mixture with a strong alkaline solution (30 to 40 B.) in such quantity as to form normal fatty acidsalts and to effect complete saponification.

5. A process for the manufacture of hard soaps having a high percentage of fatty acids corresponding to the grain soaps, consisting in effecting the saponification of fatty acids by alkali carbonates adding to the soap paste a quantity of saponifiable substance capable of increasing the resisting capacity of the alkali salts of the fatty acids to electrolytes in aqueous solution having a high percentage of fatty acids such that the fatty acid percentage of normal grain soaps is reached, and in effecting complete saponification by the addition of alkali in such quantity that after complete saponification the alkali excess of normal grain soap is present.

6. A process for the manufacture of hard soaps consisting in saponifying and graining a substance in the usual manner, eliminating the salt lye, adding to the residue a quantity of saponifiable substance capable of increasing the resisting capacity of the alkali salts of the fatty acids to electrolytes in aqueous solution, treating the mixture with caustic alkali in such quantity as is necessary for complete saponification thereof and for the formation of normal fatty acid salts from the fats or fatty acids still unsaponified, and in completing the process by a short boiling.

In testimon whereof I aflix my signature in presence 0 two Witnesses.

J OACHIM LEIMDQRFER.

Witnesses:

ARTHUR LASOLOS, JOHN J. Ron'ro. 

